Meta-owned messaging platform releases TestFlight beta update for iPhone app, introducing theme feature with customizable main colour. Users can choose from a range of five different colours to find their preferred interface. This customization addresses user concerns about the new green colour and aligns with the trend of providing more user control.Meta-owned messaging platform releases TestFlight beta update for iPhone app, introducing theme feature with customizable main colour. Users can choose from a range of five different colours to find their preferred interface. This customization addresses user concerns about the new green colour and aligns with the trend of providing more user control.